This invention relates at a method and system for determining an energy-efficient path of a machine.
A self-propelled machine for construction, agricultural, or domestic applications may be powered by an electric motor, an internal combustion engine, or a hybrid power plant that includes an electric motor and an internal combustion engine. For example, the machine may refer to an electric mower or another work vehicle for lawn and garden work. An operator of the machine may wish to cut the grass in a work area, till a garden in a work area, or accomplish some other task in the work area. If the operator manually selects a path for the machine without considering the slope of the terrain of the work area, the machine may consume greater amounts of fuel or energy that would otherwise be required. Further, if the machine is driven by an electric motor, the energy source or battery may be depleted prior to finishing the work over the entire work area. The disruption to work may cause the operator to become annoyed with electrically-propelled machines and detract from the marketability of such machines. Although a manufacturer of a machine can incorporate batteries or another energy source with greater capacity, the additional batteries may be too bulky to fit in the standard housing of the machine or may add too much weight to the machine. For example, adding too many batteries to a mower may disrupt a preferential weight distribution among the wheels and degrade the handling of the mower. Thus, a need exists for a self-propelled machine that reduces energy consumption by planning a route that considers any differences in elevation in the work area.
A method and system for determining a work path for a machine determines a path that minimizes energy consumption of the machine to enhance a usable duration of an electrical charge of an energy source or to conserve fuel. A work area is defined and is divisible into a number of cells. Respective geographic factors (e.g., elevation data) associated with corresponding cells within the work area are defined. An estimator estimates energy levels, associated with a machine moving in or between adjacent cells, in corresponding proposed directions based on at least one geographic factor (e.g., any change in elevation between or within the adjacent cells). Candidate total energy levels are determined for moving the machine through the cells along corresponding proposed work paths for the work area. A selector selects a preferential work path from the proposed work paths consistent with the determined lowest energy level of the candidate total energy levels.